This invention relates to TO-type packages and more particularly to external interfaces for TO-type packages that improve the speed of signals to and from the packages.
At the present time, the major electrical-to-optical packages utilized in the communications industry include semiconductor lasers, which may be vertical cavity surface emitting lasers (VCSELs) or edge emitting lasers. Further, these lasers are generally mounted in a sealed container, referred to in the industry as a TO-can or a TO-type package.
To provide connections to components (e.g. a VCSEL an/or a semiconductor light sensing diode) leads are provide that extend outwardly through the bottom of the TO-can. Several problems arise as a result of these leads. First, the leads must be kept straight throughout processing, shipping, storing, subsequent assembly, and other processing steps. Second, the leads must be attached by means of some external structure (e.g., a printed circuit board or flex leads) to drivers and other external circuitry. The leads generate stray capacitive and inductive circuits that produce RF losses that greatly reduce the frequency of operation (speed of the package).